1. Technical Field
The present invention pertains generally to motor vehicles. More particularly, the present invention pertains to hinged closure panels for motor vehicles. More specifically, but without restriction to the particular embodiment and/or use which is shown and described for purposes of illustration, the present invention relates to a pick-up truck having a tailgate attached to the body for rotation about a horizontal pivot axis about a lower edge of the tailgate and a centrally located, concealed hinge mechanism for permitting the tailgate to articulate between a closed position and an open position.
2. Discussion
In pick-up trucks, sport utility vehicles, station wagons, minivans and other similar vehicles having a substantially vertical rear access opening, there is often provided a tailgate assembly that is pivotably coupled to the body of the vehicle through a plurality of hinges that permit the tailgate to pivot about a horizontal pivot axis between a closed position and an open position.
Conventional tailgate hinging methods typically rely on two or more independent hinge members having a pair of leaf-members one of which is fastened to the tailgate and the other of which is fastened to the vehicle body. The independent nature of these hinges permits their axes to become skewed relative to one another due to variances in the manufacture and assembly of the vehicle body and the tailgate assembly. The skewing of the hinge axes leads to a binding condition that impairs performance of the hinges. Under extreme circumstances, the skewing of the hinge axes may cause the hinges to bind so severely as to require realignment of the hinges.
Another drawback of the conventional tailgate hinging methods concerns the conventional use of a hinge pin of a relatively small diameter and the correspondingly small surface area of the pin. As the weight of the tailgate is distributed over a relatively small surface area, stress over the surface of the hinge pin is relatively high, causing increased wear and further impairing performance.
While these drawbacks may be overlooked in vehicles which have completely manual tailgates, the need for improved performance becomes more apparent when a drive unit for automatically closing the tailgate is incorporated into the vehicle. Improved performance from the hinge assembly not only provides more reliable operation but also permits the drive unit to be down-sized to enable substantial cost savings.
Accordingly, there remains a need in the art for an improved hinge assembly for a tailgate which provides improved alignment along a central pin axis, increases the surface area over which the weight of the tailgate is distributed and provides an improved and consistent level of performance.